- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Emerging Waveguide Technology || Photonic Crystal Waveguides
摘要： The original results of theoretical and experimental studies and the properties of microwave one-dimensional waveguide photonic crystals have been generalized. Methods for describing the electrodynamic characteristics of photonic crystals and their relationship with the parameters of periodic structures filling the waveguides have been presented. The results of an investigation on the characteristics of microwave waveguide photonic crystals made in the form of dielectric matrices with air inclusions have been presented. The model of effective dielectric permittivity has been proposed for describing the characteristics of the investigated photonic crystals containing layers with a large number of air inclusions. New types of microwave low-dimensional waveguide photonic crystals containing periodically alternating elements that are sources of higher type waves have been described. The possibility of effective control of the amplitude-frequency characteristics of microwave photonic crystals by means of electric and magnetic fields has been analyzed. Examples of new applications of waveguide photonic crystals in the microwave range have been given: the measuring parameters of the materials and semiconductor nanostructures that play the role of the microwave photonic crystals' periodicity defect; the resonators of near-field microwave microscopes; small-sized matched loads for centimeter and millimeter wavelength ranges on the basis of microwave photonic crystals.
关键词： low-dimensional photonic crystal,electrically controlled characteristics,forbidden bands,defect mode,measurement of micro- and nanostructures,microwave matched loads,microwave photonic crystals
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE 14th Malaysia International Conference on Communication (MICC) - Selangor, Malaysia (2019.12.2-2019.12.4)] 2019 IEEE 14th Malaysia International Conference on Communication (MICC) - Analyzing the Effects of LED Lamp Arrangements on Performance of an Indoor Visible Light Communication System
摘要： We report the results of a study of an optical sensor based on a channel-drop technique with two cascaded cavities in photonic-crystal slabs. Quality factors and intensities of the resonant modes of the sensor were analyzed with three-dimensional simulations. With the introduction of a re?ector in the bus-channel and by control of the coupling between the two cavities and the drop-channel, the drop ef?ciency can be remarkably increased. In addition to the simulation, the two cavity sensor is fabricated and tested for optical response to water and oil in?ltration. Both direct visual imaging and quantitative analysis were applied in experiment. A difference of refractive index Δn = 0.12 between water and oil samples results in a wavelength shift of 18.3 nm, which greatly matches the simulation result of 20 nm and indicates a sensitivity of 153 nm RIU?1. Both resonant peaks for water and oil in?ltration have good selectivity in their transmission spectrum. The contrast between the broadband output of the bus-channel and the highly wavelength-selective outputs of the drop-channel opens opportunities for the two cascaded-cavity system as a fundamental building block for a multiplex drop-channel array for all-optical sensing, which can be widely used for bio/chemical detection and environmental monitoring.
关键词： optical waveguide,optical coupling,optical sensors,multiplexing,optical devices,photonic integrated circuits,photonic crystals,Cavity resonators
更新于2025-09-19 17:13:59
-
Cm-Level Photonic-Crystal-Like Subwavelength Waveguide Platform with High Integration Density
摘要： In this paper, the cm-level photonic-crystal-like subwavelength waveguide platform is developed and analyzed by using the finite-difference time-domain method. The configuration can be considered as a hybrid waveguide combining with the advantages of a metal-dielectric-metal waveguide and a photonic crystal waveguide. The symmetric and high reflection effect of metallic sidewall and the effect of the photonic crystal structure on the light-guiding mechanism and integration characteristics of the waveguide are systematically investigated. The results reveal that the cm-level photonic-crystal-like waveguide platform provides subwavelength confinement and very low propagation loss with the isolation more than 30 dB, which are promising for high-density photonic integration. The tradeoff between integration density and propagation loss is optimized. In addition, a T-shaped power splitter based on the waveguide platform is proposed. The excess loss of the T-shaped power splitter is less than 0.4 dB. A set of passive components can be exploited on the proposed cm-level photonic-crystal-like subwavelength waveguide platform in future work to constitute the large-scale integrated photonic systems.
关键词： integrated optics,photonic crystals,waveguide splitter,subwavelength waveguides
更新于2025-09-19 17:13:59
-
Efficient Low-Cost All-Flexible Microcavity Semitransparent Polymer Solar Cells Enabled by Polymer Flexible One-Dimensional Photonic Crystals
摘要： High-efficiency low-cost all-flexible microcavity semitransparent polymer solar cells (STPSCs) are comparatively studied in both fullerene- and nonfullerene-based systems with the structure strategy employing polymer flexible one-dimensional photonic crystals (F-1DPCs), as well as ITO-free UV/ozone plasma-treated polymer/ultrathin metal and PEDOT:PSS transparent electrodes. Based on the reasonable optimization of electrical and optical characteristics in device, the maximum power conversion efficiency with the use of polymer F-1DPCs can be greatly improved by 24~27% compared to the respective control devices. The improvement in JSC is comprehensively discussed, which is mainly ascribed to the enhancement of effective photon absorption in device. Although color tunability of fullerene and nonfullerene all-flexible STPSCs can be easily achieved with the use of different photonic bandgaps of polymer F-1DPCs, the CIE coordinates of nonfullerene STPSCs differ a lot from the original light source compared to the fullerene ones due to a high absorption coefficient in a narrow wavelength region. This work presents an easy and effective microcavity device strategy incorporated with different elements and demonstrates a new sketch of structure-absorption-performance relationships for fullerene- versus nonfullerene-based all-flexible STPSCs, which is compatible with low-cost roll-to-roll manufacturing and surely has a diversity of potential applications to better meet specific needs.
关键词： all-flexible,polymer solar cell,semitransparent,polymer flexible one-dimensional photonic crystals,microcavity
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE 16th International Conference on Group IV Photonics (GFP) - Singapore, Singapore (2019.8.28-2019.8.30)] 2019 IEEE 16th International Conference on Group IV Photonics (GFP) - Photoluminescence Enhancement Phenomena in Photonic Crystal Slabs Formed on Si Structures with the Self-Assembled Ge Nanoislands
摘要： The strong enhancement of photoluminescence intensity was observed in photonic crystal slabs realized on Si structures with the self-assembled Ge nanoislands. The observed phenomena are described in terms of the nanoislands – photonic crystal modes interaction.
关键词： Ge nanoislands,bound state in the continuum,photonic mode,photonic crystals,photoluminescence
更新于2025-09-16 10:30:52
-
[IEEE 2019 IEEE 16th International Conference on Group IV Photonics (GFP) - Singapore, Singapore (2019.8.28-2019.8.30)] 2019 IEEE 16th International Conference on Group IV Photonics (GFP) - Photoluminescence Enhancement Phenomena in Photonic Crystal Slabs Formed on Si Structures with the Self-Assembled Ge Nanoislands
摘要： The strong enhancement of photoluminescence intensity was observed in photonic crystal slabs realized on Si structures with the self-assembled Ge nanoislands. The observed phenomena are described in terms of the nanoislands – photonic crystal modes interaction.
关键词： Ge nanoislands,photonic crystals,bound state in the continuum,photoluminescence,photonic mode
更新于2025-09-16 10:30:52
-
All-optical OR/XOR logic gate using PhC-based T-shaped waveguide with high-contrast output to implement 3-bit binary to gray code converter
摘要： In this article, a theoretical analysis on T-shaped waveguide is performed using coupled mode theory which admits its operation as power combiner, splitter and diverter. These applications of the waveguide can very well be utilized to project it as OR and XOR logic gates. In order to achieve this, the T-shaped waveguide is mapped onto the photonic crystal of square-type lattice and the validity is observed with the theoretical analysis. Later, the designed T-shaped waveguide is used to define OR and XOR gates, which results in the contrast ratio and response time of 54.43 dB and < 1 ps, respectively, at 1550 nm. Further, the higher contrast ratio of the T-shaped waveguide-based XOR logic gate allows it to cascade with itself in a single stage to realize a 3-bit binary to gray code converter. The simulation results show that the code converter operates with contrast ratio of above 9.82 dB at the output ports. Finally, the fair results obtained from theoretical analysis and numerical simulation conclude that the T-shaped waveguide can be a potential component as logic gate in the future photonic integrated circuits.
关键词： Photonic crystals,Binary to gray code converter,Optical computing,T-shaped waveguide
更新于2025-09-16 10:30:52
-
[IEEE 2019 TEQIP III Sponsored International Conference on Microwave Integrated Circuits, Photonics and Wireless Networks (IMICPW) - Tiruchirappalli, India (2019.5.22-2019.5.24)] 2019 TEQIP III Sponsored International Conference on Microwave Integrated Circuits, Photonics and Wireless Networks (IMICPW) - Design of GaAs-Photonic Crystal Based Polarization Splitter
摘要： Photonic Crystal has attracted many researchers because of their distinctive capabilities, larger application areas. In this paper, a polarization splitter based on photonic crystal is developed with the help of photonic band gap diagram and self-collimation method. The photonic crystal based splitter is constructed in hexagonal lattice structure with GaAs rods placed in air. To obtain the band diagram, the radius of the rods is considered as 100 nm with lattice constant of 500nm. The developed polarization splitter is simulated using RSOFT software. It is observed through the simulation results that Cthe proposed splitter design achieves better transmission spectral and optical field distributions for both TE and TM modes. Power dissipation is reduced compared to that of existing splitters. 90% transmission is obtained for the proposed model.
关键词： Polarization splitter,Photonic crystals,GaAs
更新于2025-09-16 10:30:52
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Placing Quantum Dots in 3D Photonic Crystals and Finding Them Back
摘要： It is a major outstanding goal in Nanophotonics to precisely place quantum emitters inside a three-dimensional (3D) metamaterial. It is well-known that such control offers exquisite control over cavity QED, spontaneous and stimulated emission, and even non-linear optics. Theory predicts that the emission of an emitter, e.g. a quantum dot, varies spatially on 100s nm scale. Thus, the challenge is to place emitters with a precision better than Δx < 100 nm. We present our newly developed chemical toolbox to fix the positions of quantum dots with a polymer brush layer with thicknesses in the 10s nm range in silicon nanostructures. Once 3D positioning is successful, a second challenge arises, namely how to non-destructively find where the emitter sits in the 3D structure. Since nanophotonic materials are necessarily opaque, optical microscopy has insufficient penetration depth, apart from its limited resolution. While scanning electron microscopy (SEM) offers sufficient spatial resolution, it has a small penetration depth hence only the sample surface is viewed but not the bulk. X-ray techniques are promising tools, in view of excellent penetration depth, non-destructive character, and nm spatial resolution. Therefore, we study a 3D Si photonic band gap crystal with infiltrated PbS nanocrystal quantum dots by X-ray fluorescence tomography. Our photonic crystals have the inverse woodpile structure that exhibits a broad full and complete 3D band gap. The crystal are made by CMOS-compatible methods using deep reactive ion-etching through tailored masks. Fluorescence tomography was performed at the ESRF (beamline ID-16NI). X-rays (17 keV photon energy) are focussed in the sample. We collect data at 17 different angles while rotating the crystal from 0 to 180°. Projection maps are obtained at every angle, followed by standard tomographic reconstruction to obtain the 3D atom density distribution with 50 nm spatial 3D resolution for each chemical element. Fig. 1(B) shows a projection map of the number of lead atoms - from the quantum dots - in one crystal. The volume is a cube that contains the 3D photonic crystal structure that is surrounded by bulk silicon above and by the 2D array of deep pores that are etched first. Close inspection of the 3D volume after reconstruction indeed reveals two sets of pores running in the Z and the X-directions, matching the design (Fig. 1(A). The structure is periodic with lattice parameters that also match the design very well. It appears that the quantum dots are located throughout the whole crystal volume. Their position correlates well with elements characteristic of the polymer brush layer. Finally, we find that after the X-ray experiment the quantum dots remain optically active. We conclude that 3D X-ray fluorescence tomography has great potential to solve many future questions on 3D optical metamaterials for nanophotonic research and applications, including cavity arrays, physically unclonable functions, and precise localization of light emitters as qubits and for enhanced lighting efficiency.
关键词： nanophotonics,polymer brush layer,quantum dots,3D photonic crystals,X-ray fluorescence tomography
更新于2025-09-16 10:30:52
-
[IEEE 2019 IEEE 2nd International Conference on Electronics Technology (ICET) - Chengdu, China (2019.5.10-2019.5.13)] 2019 IEEE 2nd International Conference on Electronics Technology (ICET) - Light Outcoupling Integrated Photonic Crystals for OLEDs
摘要： To develop an efficient light outcoupling strategy to improve the efficiency and viewing of organic light emitting diodes (OLEDs) could be beneficial for display application. We propose a hybrid mode formed by integrating a photonic crystal structure on the semitransparent metal electrode of OLEDs to enhance the light outcoupling efficiency and viewing characteristics. The hybrid mode was realized through excite both tamm plasmon mode and microcavity mode.
关键词： OLEDs,tamm plasmon,photonic crystals,light outcoupling
更新于2025-09-16 10:30:52